Multi-purpose food processor

ABSTRACT

A multi-purpose kitchen appliance comprising a first container closable by a cover in which a first driven working utensil can be inserted for processing food stuffs which can be coupled via a first connector with a drive spindle projecting through the base of the electric motor in the multi-purpose kitchen appliance. A second, smaller container may be inserted into the first container. A second utensil in the second container can be coupled to the drive spindle via a second connector. A sealing lip is arranged on the edge of the aperture of the second container which, when the latter is inserted in the first container, forms a seal on the underside of the cover when the cover is fitted on the first container.

This invention relates to a multi-purpose food processor having a firstcylindrical container adapted to be closed by a cover and suitable forinsertion of a first driveable processing tool for processing foodmaterials, the first tool being adapted to be coupled by means of afirst coupling device to a driving shaft which extends through thebottom of the first container and is adapted to be driven by an electricmotor arranged in the housing of the multi-purpose food processor, witha second cylindrical container of a smaller volumetric capacity beinginsertable into the first container prior to it being closed, and with asecond driveable processing tool being insertable through a secondcontainer filler opening for processing food materials of smallerquantities, the second tool being adapted to be coupled to the drivingshaft by means of a second coupling device, and with the cover, onclosing the first container, closing at the same time the filler openingof the second container.

A multi-purpose food processor is already known from U.S. Pat No.4,586,666. When it is desired to chop small quantities of foodstuffs as,for example, parsley or onions, this is hardly possible in the firstlarge-volume container because in the processing of small quantities offood, these are flung against the large inner wall surface of the firstcontainer, clinging thereto or collecting on the bottom, so that thecutting blade arranged at a small relative distance to the inner walland the bottom of the first container is then no longer in a position toseize the food for further processing. To avoid this, a second containerof smaller volumetric capacity is inserted into the first container toenable also very small quantities of food to be chopped sufficientlywell.

To prevent the food items contained in the second container from beingexpelled into the first container during processing, the secondcontainer is closed by a second lid. Not only does the second lidincrease the manufacturing cost of the multi-purpose food processor, italso makes manipulation more difficult, since it invariably requires thesecond lid to be placed down on the second container, in addition tosetting the first lid in place. For example, in the event of anoperator's failure to place the second lid down onto the secondcontainer, the food material is also expelled into the first container,making processing impossible, apart from contaminating the firstcontainer.

Further, from WO 89/00827 a food processor according to the prior-artportion of claim 1 is known in which a second container of asubstantially smaller diameter than the first container sitsnon-rotatably on the forward end of a sleeve centrally disposed in thefirst container. When the first container is closed by the lid in thismulti-purpose food processor, the free rim of the second containerbecomes engaged by an annular collar formed on the underside of the lid,causing also the second container to be closed by the lid.

In this known multi-purpose food processor, it is to be considered lessadvantageous that the manufacturing tolerances occurring in themanufacture of the containers and the lid make it impossible in practiceto effectively close the second container by the lid, because both thedimension between the outer wall of the second container and the annularcollar on the lid in the radial direction and the dimension between therim of the second container and the underside of the lid in the axialdirection will practically never be able to be zero millimeters, so thata clearance is invariably present. This clearance allows the passage offood materials. Accordingly, when mixing drinks in the second containeror processing condiments to a very fine degree (powdery), not only theliquid but also the processed food items will find their way over theupper rim of the second container into the first container. Due to theinevitable clearance between the annular collar on the lid and the rimof the second container, vibrations occurring on the second containerduring the processing operation are transmitted through the rim to theannular collar of the lid, producing an unpleasant rattling or runningnoise level in this multi-purpose food processor.

It is therefore an object of the present invention to provide amulti-purpose food processor in which the above-mentioned disadvantages,particularly the passage of food material from the second container intothe first container, are eliminated and in which vibrations occurring onthe first and second container during the processing of food materialsare absorbed by the second container in a simple manner, thus avoidingnoise.

According to a first embodiment of the present invention, this object isaccomplished in that a circumferential, resiliently deformable sealinglip is arranged on the second container in the area of the filleropening, and that the sealing lip, with the second container nestedwithin the first container and the cover closing the first container, isresiliently deformed by the underside of the cover such as to be insealing engagement with the underside of the cover. The provision of aresiliently deformable sealing lip on the second container eliminatesentirely any leakage between the cover and the second container duringoperation of the multi-purpose food processor, thus avoidingcontamination of the first container by the food materials processed inthe second container. Any vibrations acting on the container during theprocessing of food items are largely absorbed by the sealing lip, thusmaking for a substantially quieter running of the multi-purpose foodprocessor of the invention also in cases where both containers arenested within each other. The sealing lip affords particular ease ofmanufacture when it is arranged on the rim bounding the filler openingof the second container.

To ensure an optimum and resilient deformation of the sealing lip, thesealing lip diverges outwardly in conical fashion. However, it can alsobe considered that the sealing lip tapers conically inwardly, or thatthe sealing lip is formed by an annular torus becoming radially orlaterally expanded or deformed by the axial compression force of thesecond container.

The sealing lip may be fitted to the end remote from the secondcontainer in a subsequent operation with particular ease. However, itmay also be contemplated to provide the sealing lip on the outer wall oron the inner wall of the second container from where it then extends upto the cover.

In a further feature of the present invention, the sealing lip isaffixed to the rim of the second container in a particularly simplemanner by hot-molding it thereto. This may be accomplished applyingeither the single- or the two-component molding technique, thesingle-component molding technique involving hot-molding of the sealinglip onto the cold rim after molding of the second container, thusproducing an intimate connection by fusing the rim of the secondcontainer. In the two-component molding technique, after molding thesecond container the mold is changed on the same molding machine tosubsequently hot-mold the sealing lip onto the still warm rim of thesecond container. It will be understood that it may also be consideredto join the sealing lip to the rim of the second container following itsmolding by adhesive bonding or to cold-mold it thereon, for example, bymeans of silicone, etc.

As a material for the application of the above-mentioned moldingtechnique for manufacturing the sealing lip, a thermoplastic elastomerhas proven to be particularly advantageous, while the second containeris made of polypropylene which cures after being hot-molded and is rigidwhen cold, having accordingly only little resilience.

In a second embodiment of the present invention, it is particularlyadvantageous that a resiliently deformable sealing lip projects from thecover in the area of the rim of the filler opening of the secondcontainer, and that the sealing lip, with the second container nestedwithin the first container and the cover closing the first container, isresiliently deformed by the rim of the second container such as to be insealing engagement with the rim of the second container.

By providing the sealing lip on the underside of the cover, a seal ofequally good quality results between the cover and the second container.In this embodiment, too, the resiliently deformable sealing lip may beof a conically diverging or conically tapering configuration. It mayalso be considered that provision is made for a respective resilientlydeformable sealing lip on both the cover and the second container, thelips acting on each other in a sealing manner following their resilientdeformation when the second container is used.

Advantageously, both embodiments provide a first aperture in the bottomof the first container, the first aperture is surrounded by a firstsleeve projecting into the first container, the driving shaft extendsinto the first sleeve, a second aperture is provided in the bottom ofthe second container, the second aperture is surrounded by a secondsleeve projecting into the second container, the second container isseatable on the free end of the first sleeve, the second coupling deviceof the second processing tool is comprised of a tube which extendsthrough the second sleeve, is seatable on the free end of the drivingshaft and encompasses it, the tube being adapted to be coupled to thedriving shaft in a non-rotating relationship by an engagement meansprovided between the driving shaft and the tube. This enables the secondcontainer to be directed to the driving mechanism with particular ease,and the second container seats and centers on the first containerreadily, so that the sealing lip is at all times in uniform engagementwith the cover. Good centering and mounting of the second container onthe first container in a non-rotatable relationship is accomplished byproviding in the bottom a tubular well with teeth for receiving the freeend of the first sleeve, the teeth meshing with teeth provided on thefirst sleeve.

To ensure that the drive motor is not energized until the cover isclosed to prevent injury when using a cutting blade as the processingtool, a further feature of the invention provides an actuating camformed on the cover to unlock an interlocking device arranged in themulti-purpose food processor when the first container is closed, so thatthe electric motor cannot be energized until the first container issecurely closed.

To be able to introduce food materials into the closed second containerthrough the feed channel, the cover advantageously includes a feedchannel for filling food into the container, and the feed channel ismounted on the cover such that its imaginary extension opens into thesecond container.

A sole embodiment of the present invention is illustrated in theaccompanying drawing and will be described in more detail in thefollowing.

The sole FIGURE shows in longitudinal section only the containerarrangement, while the remainder of the multi-purpose food processor asknown, for example, from GB-2 177 289 A and as suitable for applicationto the container arrangement of the invention, is not illustrated forreasons of simplicity.

The first container 1 comprises a wall 2 of circular cross section inthe form of a hollow cylinder. The bottom 3 of the first container 1includes a first aperture 4 closed off by a first sleeve 6 projectinginto the container interior 5 in order to prevent liquid food fromleaking out of the container when the liquid is below a maximum fillinglevel. The maximum filling level of the first container 1 thuscorresponds to the free end 7 of the first sleeve 6.

Integrally formed on the outer wall 8 of the first container 1 is aU-shaped handle 9 shown only in fragments. Adjoining the bottom 3 indownward direction when viewing the drawing is an annular collar 10which serves a centering function when the first container 1 is seatedon a drive structure, not shown, of a multi-purpose food processor.

The first container 1 is lockable by means of a bayonet catch 12provided on the cover 11. With the cover properly locked in place, anactuating cam 13 projecting radially on the cover 11 engages into aslot, not shown, on the multi-purpose food processor, thereby unlockingan interlocking device which is the prerequisite for starting operationof the food processor.

Radially outside the center 14 of the cover 11, a tubular feed channel15 extends upwardly when viewing the drawing, the feed channel servingto introduce food materials into the container successively duringoperation of the multi-purpose food processor, to be subsequentlyprocessed or chopped by the first or second processing tool. In thecenter of the cover 11, a centering device 16 is provided which servesthe function of centrally locating the free end of a processing toolproducing a major tilting moment, such as dough hook, shredding disk,etc., which however cannot be inserted into the first container 1because the second container 20 is nested within the first container 1.To enable the cover 11 to be readily centered when placed down on thefirst container 1, an annular collar 18 extending into the containerinterior and resting against the inner wall 17 thereof is integrallyformed on the cover 11.

The bottom 19 of the second container 20 bears against the free end 7 ofthe first sleeve 6, centering itself by means of a bore 21 provided inthe bottom 19 of the second container 20 and formed by a tubular well22. Teeth 46 are provided radially within the bore 21. Extending fromthe bottom 19 into the container interior 23 is a second sleeve 24closing off the second aperture 25 provided in the bottom 19 of thesecond container 20, so that only food that exceeds the maximum fillinglevel may escape through the free end 26 of the second sleeve 24. Theteeth 46 are in mesh with teeth 47 formed on the first sleeve 6 in anon-rotating relationship to lock the container 20 against rotation.

Adjoining the bottom 19 of the second container 20 in downward directionwhen viewing the drawing is a second annular collar 27 of a diametercorresponding essentially to that of the tubular wall 28 of the secondcontainer 20 and terminating with its free end level with, or slightlybeyond, the free end of the tubular well 22, thereby ensuring a safesupporting surface for the second container 20. Rib members 30 spacedover the circumference and extending in longitudinal direction parallelto the center line 14 are arranged on the inner wall 29 of the secondcontainer 20.

Molded onto the end 31 bounding the second container 20 in upwarddirection is a resilient sealing lip 32 which diverges conically towardsthe cover 11 and is in sealing and slightly biased engagement with theunderside 33 of the cover 11 proximate to the container interior 23 ofthe second container 20, thereby closing the filler opening 34 and thusthe second container 20 from above. While the rim 35 extends in themanner of a circular ring in the area of the end 31 of the secondcontainer 20 outside the feed channel 15, it widens by means of theconical surface area 36 in order to ensure that the feed channel 15arranged outside the center 14 opens exclusively into the secondcontainer 20 when in use. Also the sealing lip 32 widens in this area,thus resting flush against the cover 11.

Underneath the bottom 3 of the first container 1, a driving shaft 37coupled to the drive mechanism of the food processor projects into thefirst aperture 4, the shaft extending through the first sleeve 6 andhaving an engagement means at its free end in the form of a hexagon 38.Seated on the hexagon 38 in a non-rotatable relationship is a tube 40equally provided with a hexagon 39 and connected by means of a bridgemember 41 to a second tube 42 concentrically surrounding the secondsleeve 24 from outside. The second tube 42 terminates in close proximityto the bottom 19 of the second container 20. Two crescent-shaped cuttingblades 43 are secured to the second tube 42. The cutting blades 43 arearranged in a diametrically opposite relationship on the second tube 42and are molded integrally with the second tube 42 if the two tubes 40,42 are integrally molded of plastics. The parts 40, 41, 42 and 43combine to form a processing tool 44 for the second container 20. Withthe free end of the first tube 40, the processing tool 44 takes supportupon a step 45 provided on the driving shaft 37.

The mode of operation of the multi-purpose food processor of the presentinvention is as follows:

When it is desired to chop, mix or knead major quantities of foodmaterials, only the first container 1 is used. The processing tool (notshown) is then placed into the first container 1 having the largerdimensions and is seated down onto the driving shaft 37. After the cover11 is closed, processing of the food materials may be started.

When it is desired to chop only very small quantities of food as, forexample, parsley, onions, garlic, etc., the second container 20 is setin place on the first sleeve 6 such that the bottom 19 bears against thefree end 7 of the first sleeve 6, causing the tubular well 22 tosurround the first sleeve 6 concentrically. Subsequently, the processingtool 44 suitable for the second container 20 is coupled to the drivingshaft 37. The next step involves seating the cover 11 on the firstcontainer 1 such as to enable the bayonet catch 12 to engage theinterlocking device of the food processor. At the same time, theunderside 33 of the cover will engage the free end of the sealing lip 32which will experience a slight outward and downward pressure and, asthis occurs, a biasing force until the cover 11 has reached its properlocked position. At this instant, the cover 11 will have closed both thefirst and the second container 1, 20.

Food materials may then be introduced through the feed channel 15, to besubsequently chopped by the processing tool 44 rotated by the drivingshaft 37 on turning on the food processor. Owing to the small diameterand the low height of the second container 20 (low volumetric capacity),all food materials, no matter how small, will be seized by the cuttingblades 43 which are at a very small distance to the container wall 28and the bottom 19. This effect is further enhanced by the rib members 30provided on the second container 20, as they decelerate the food rotatedby the processing tool 44, directing it back again to the cutting blades43.

We claim:
 1. A multi-purpose food processor comprising a firstcylindrical container, a driving shaft extending through the bottom ofsaid first container and adapted to be driven by an electric motorarranged in said multi-purpose food processor, said driving shaft havinga first coupling device for receiving of a first driveable food materialprocessing tool suitable for insertion in said first container andcoupling said first tool to said driving shaft, a cover for said firstcontainer, a second cylindrical container of smaller volumetric capacitythan said first container, said second container being insertable intosaid first container prior to said first container being closed by saidcover, said second container having a filler opening, a second driveableprocessing tool adapted to be inserted through said second containerfiller opening for processing food materials of smaller quantities, asecond coupling device for coupling said second tool to said drivingshaft, said cover, on closing said first container, closing at the sametime said second container filler opening, and a circumferential,resiliently deformable sealing lip structure on said second container inthe area of said second container filler opening, said sealing lipstructure diverging outwardly in conical fashion, said sealing lipstructure with said second container nested within said first containerand said cover closing said first container being resiliently deformedby the underside of said cover such as to be in sealing engagement withsaid underside of said cover.
 2. A multi-purpose food processorcomprising a first cylindrical container, a driving shaft extendingthrough the bottom of said first container and adapted to be driven byan electric motor arranges in said multi-purpose food processor, saiddriving shaft having a first coupling device for receiving a firstdriveable food material processing tool suitable for insertion in saidfirst container and coupling said first tool to said driving shaft, acover for said first container, a second cylindrical container ofsmaller volumetric capacity than said first container, said secondcontainer being insertable into said first container prior to said firstcontainer being closed by said cover, said second container having afiller opening, a second driveable processing tool being adapted to beinserted through said second container filler opening for processingfood materials of smaller quantities, a second coupling device forcoupling said second tool to said driving shaft, said cover, on closingsaid first container, closing at the same time said second containerfiller opening, said second container filler opening having a rim, aresiliently deformable sealing lip structure projecting from said coverin the area of said rim of said filler opening of said second container,said sealing lip structure diverging outwardly in conical fashion andbeing resiliently deformed by said rim of said second container and insealing engagement with said rim of said second container when saidsecond container is nested within said first container and said covercloses said first container.
 3. The multi-purpose food processor ofclaim 1 wherein said second container filler opening has a rim and saidresiliently deformable sealing lip structure is arranged on said rim. 4.The multi-purpose food processor of claim 3 wherein said rim has an edgeportion, and said resiliently deformable sealing lip structure isaffixed to said edge portion of said rim.
 5. The multi-purpose foodprocessor of either claim 3 or 4 wherein said resiliently deformablesealing lip structure is hot-molded onto said rim.
 6. The multi-purposefood processor of claim 2 wherein said resiliently deformable sealinglip structure is hot-molded onto the underside of said cover.
 7. Themulti-purpose food processor of claim 2, 3, or 4 wherein saidresiliently deformable sealing lip structure is made of a thermoplasticelastomer on a polypropylene base, and said second container is made ofpolypropylene.
 8. The multi-purpose food processor of either claim 1 or3 wherein a first aperture is provided in the bottom of said firstcontainer, said first container includes a first sleeve that projectsinto said first container and surrounds said first aperture, saiddriving shaft extends into said first sleeve, a second aperture isprovided in the bottom of said second container, said second containerincludes a second sleeve that projects into said second container andsurrounds said second aperture, said second container is seatable on thefree end of said first sleeve, and said second coupling device includestube structure that is adapted to extend through said second sleeve andto seat on and encompass the free end of said driving shaft, said tubestructure including engagement means adapted to be coupled to saiddriving shaft in a non-rotating relationship.
 9. The multi-purpose foodprocessor of claim 8 and further including bore structure in said bottomof said second container for receiving the free end of said firstsleeve.
 10. The multi-purpose food processor of either claim 1 or 2wherein said first processing tool is a cutting blade.
 11. Themulti-purpose food processor of either claim 1 or 2 and furtherincluding an inter-locking device in the multi-purpose food processorand an actuating cam on said cover for unlocking when said firstcontainer is closed, so that the electric motor cannot be energizeduntil said first and said second containers are securely closed by saidcover.
 12. The multi-purpose food processor of either claim 1 or 2wherein said cover includes feed channel structure for introducing foodinto said containers, said feed channel structure being disposed on saidcover such that an imaginary extension of said feed channel extends intosaid second container.